Question

最近开始处理现有项目，该项目严重依赖awesome_nested_set gem并使用其中一种方法self_and_descendants引用here

此方法在拉动所有子项方面过于繁重，并触发了许多查询。我已经建立了索引，但正在寻找替代方案来解决这个性能问题。

触发的示例Sql

q = Group.first
q.self_and_descendants

以上代码触发了以下查询，还有更多只有一些被粘贴

  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2231
  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2233
  Group::Translation Load (0.4ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2239
  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2240
  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2241
  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2242
  Group::Translation Load (0.3ms)  SELECT `group_translations`.* FROM `group_translations` WHERE `group_translations`.`group_id` = 2252

Answer 1

花了一些时间后没有回复。 :)我做了这件事。

class Group < ActiveRecord::Base
acts_as_nested_set

 def self_and_descendants_hashed
    ActiveRecord::Base.connection.select_all("SELECT * FROM groups WHERE lft >= #{self.lft} AND rgt <= #{self.rgt} order by lft")
  end
end

令人敬畏的嵌套集：self_and_descendants的性能改进

1 个答案: